Contemporary treatment trends for upper urinary tract stones in a total population analysis in Germany from 2006 to 2019: will shock wave lithotripsy become extinct?

Ultrasound-mediated nanomaterials for the treatment of inflammatory diseases

Sterile and infection-associated inflammatory diseases are becoming increasingly prevalent worldwide. Conventional drug therapies often entail significant drawbacks, such as the risk of drug overdose, the development of drug resistance in pathogens, and systemic adverse reactions, all of which can undermine the effectiveness of treatments for these conditions. Nanomaterials (NMs) have emerged as a promising tool in the treatment of inflammatory diseases due to their precise targeting capabilities, tunable characteristics, and responsiveness to external stimuli. Ultrasound (US), a non-invasive and effective treatment method, has been explored in combination with NMs to achieve enhanced therapeutic outcomes. This review provides a comprehensive overview of the recent advances in the use of US-mediated NMs for treating inflammatory diseases. A comprehensive introduction to the application and classification of US was first presented, emphasizing the advantages of US-mediated NMs and the mechanisms through which US and NMs interact to enhance anti-inflammatory therapy. Subsequently, specific applications of US-mediated NMs in sterile and infection-associated inflammation were summarized. Finally, the challenges and prospects of US-mediated NMs in clinical translation were discussed, along with an outline of future research directions. This review aims to provide insights to guide the development and improvement of US-mediated NMs for more effective therapeutic interventions in inflammatory diseases.

Overview of Therapeutic Ultrasound Applications and Safety Considerations: 2024 Update

A 2012 review of therapeutic ultrasound was published to educate researchers and physicians on potential applications and concerns for unintended bioeffects (doi: 10.7863/jum.2012.31.4.623). This review serves as an update to the parent article, highlighting advances in therapeutic ultrasound over the past 12 years. In addition to general mechanisms for bioeffects produced by therapeutic ultrasound, current applications, and the pre-clinical and clinical stages are outlined. An overview is provided for image guidance methods to monitor and assess treatment progress. Finally, other topics relevant for the translation of therapeutic ultrasound are discussed, including computational modeling, tissue-mimicking phantoms, and quality assurance protocols.

Adverse events related to laser fibers and laser machines during ureteroscopy and stone lithotripsy: Insights from an updated 10-year analysis of the US MAUDE database

INTRODUCTION

Ureteroscopy has become increasingly chosen as a treatment of choice for patients with kidney stone disease and laser as the energy source for stone lithotripsy is a key part of this. Our aim was to analyse a national database to evaluate the burden of adverse events related to laser fibers and laser machines.

METHODS

Search was performed of the Manufacturer User and Facility Device Experience (MAUDE) database in the United States for all events related to holmium laser fibers and holmium laser machines during ureteroscopy between 2012-2021. Information collected included the following: problem, timing, prolonged anaesthesia, early termination of procedure, injury and retained parts.

RESULTS

699 holmium laser fiber events were reported and these had been manufactured by 13 different companies. The commonest problems were breakage outside the patient while in use (26.3%) and breakage of the laser fiber tip (21.2%). Manufacturers concluded root cause to be device failure in 8.9%. 29% of issues occurred before the laser had been activated. 5.2% of cases had to be cancelled as a result of an event. Significantly more injuries were sustained intra-operatively by operating staff compared to patients (6% vs. 0.2%, p < 0.001). All these injuries were superficial burns to the skin with the hand being the most affected body part (88.1%). Zero ocular injuries were reported. Only eight events were related to laser machines and all involved sudden hardware failure but no patient injury.

CONCLUSIONS

Laser fibers are fragile. Most adverse events are due to operator error. Direct patient injury from laser fiber is scarce but operating staff should be aware of the risk of sustaining minor burns. Laser machines rarely incur problems and, in this study, did not result in any safety issues beyond need to abort the procedure due to lack of spare equipment.

Endourological society fellowship program: a real contribution to improve surgical outcomes of stone patients treated with ureteroscopy

PURPOSE

We assessed the impact of the one-year endourological society fellowship program (ESFP) on the achievement of optimal surgical outcomes (OSO) in stone patients treated with ureteroscopy (URS).

MATERIALS AND METHODS

We identified 303 stone patients treated with URS from January 2018 to June 2022 by five experienced surgeons (ES). Of those, two attended ESFP. OSO was defined as the presence of residual fragments ≤ 4 mm at 1-month post-operative imaging (Ultrasound + X - Ray or CT scan). Descriptive statistics explored patients' characteristics and the rate of OSO according to the attendance of ESFP. Uni- and multivariate logistic regression analyses (UVA and MVA) tested the impact of stone characteristics, surgical data, ESFP, and imaging technique on the rate of OSO. The LOWESS curve explored the graphical association between stone size and the multivariable-adjusted probability of OSO in the two groups of surgeons.

RESULTS

Of 303 patients, 208 (69%) were treated by the two surgeons who attended ESFP. OSO was achieved in 66% and 52% of patients treated by ES with and without ESFP, respectively (p = 0.01). At UVA, ESFP (OR = 1.78; 95% CI = 1.09-2.90), stone diameter (OR = 0.92; 95% CI = 0.88-0.96), stone location (kidney vs. ureter; OR = 0.34; 95% CI = 0.21-0.58), imaging technique (CT scan vs. Ultrasound + X-Ray; OR = 0.28; 95% CI = 0.16-0.47) predicted OSO achievement (all p < 0.05). At MVA analyses, ESFP was associated with OSO (OR = 2.24; 95% CI = 1.29-3.88; p < 0.05), along with the other aforementioned variables. The LOWESS curve showed that the greater the stone size, the greater the difference in OSO in the two groups of surgeons.

CONCLUSIONS

ESFP positively affects OSO achievement after URS, especially in patients with a high stone burden.

Japanese survey of perioperative complications and ureteral stricture after ureteroscopy with laser lithotripsy for upper urinary tract stones in multicenter collaborative study

OBJECTIVES

This study aimed to investigate perioperative complications and the details of postoperative ureteral stricture after ureteroscopy with laser lithotripsy (URS-L) for upper urinary tract stones in Japan.

METHODS

Patient data on intra- and postoperative complications after ureteroscopy using URS-L were retrospectively collected from multiple centers in Japan between April 2017 and March 2020 with the cooperation of the Japanese Society of Endourology and Robotics. Data included the number of patients undergoing URS-L, number and type of intra- and postoperative complications, and detailed characteristics of postoperative ureteral stricture.

RESULTS

In total, 14 125 patients underwent URS-L over 3 years at 82 institutions. Annual URS-L numbers gradually increased from 4419 in 2017, to 4760 in 2018, and 4946 in 2019. The total complication rate was 10.5%, which was divided into intra-operative complications in 1.40% and postoperative complications in 9.18%. The annual incidences of intra- and postoperative complications were not significantly different from year to year (p = 0.314 and p = 0.112). Ureteral perforation, ureteral avulsion, and the intra-operative conversion rate were 1.35%, 0.03%, and 0.02%, respectively. Fever >38°C, septic shock, blood transfusion, and postoperative mortality were 7.44%, 0.81%, 0.07%, and 0.04%, respectively. Ureteral stricture occurred in 0.8% of cases. The median length of stricture site was 10.0 mm and the success rate of stricture treatment was 54.6%.

CONCLUSION

Although URS-L utilization has increased in Japan, the annual complication rate has remained steady. Although URS-L is a useful and less invasive procedure, devastating complications can still occur.

Treatment trends for undescended testis and impact of guideline changes a medical health care analysis of orchidopexy and cryptorchidism in Germany between 2006 und 2020

BACKGROUND

The last decades revealed new scientific knowledge regarding the fertility and potential malignancy of undescended testis AQ2(UDT). Accordingly, many guidelines changed their recommendation concerning timing of therapy, with the goal of an earlier time of surgery.

METHODS

We analyzed the number of new diagnosis and performed surgeries in predefined age groups provided by the obligatory annual reports of German hospitals in the reimbursement.INFO"-tool between 2006 and 2020.

RESULTS

Overall, 124,741 cases were analyzed. We showed a slight increase in performed surgeries in the first year by 2% per year with a main increase till 2011, a constant number of surgeries between first and 4th year and a decrease of surgeries between 5 and 14th year of living with a main decrease till 2009 by 3% per year.

CONCLUSION

Even if our results illustrate an increasing adaption of the guideline's recommendation, there is still a significant number of patients who receive later treatment. More research about the reasons and circumstances for the latter is needed.

Temperature Measurements During Flexible Ureteroscopic Laser Lithotripsy: A Prospective Clinical Trial

Objective: The primary aim of the study was to explore intrarenal temperatures (IRTs) during flexible ureteroscopic laser lithotripsy (FURSL). The secondary aim was to investigate the correlation between temperatures and renal pelvis anteroposterior diameter (APD). Materials and Methods: From February 2023 to June 2023, 10 patients with an indwelling nephrostomy tube (NT) undergoing FURSL were enrolled in the study. Sheathless FURSL was performed using gravitational irrigation (23°C) at 60 cm. A sterile K-type thermocouple was inserted through the NT. Temperatures were recorded for 120 seconds with continuous laser activation and for another 60 seconds after deactivation. Thulium fiber laser delivered energy using a 150 μm fiber and incremental power settings of 5, 10, 20, and 30 W. The laser was deactivated whenever the IRT reached 43°C. Results: IRT correlated directly to power settings. Each time the power settings were increased, the temperature rose significantly. The increase in average peak temperature was 2.6°C between 5 and 10 W (p < 0.001), 3.4°C between 10 and 20 W (p < 0.001), and 2.5°C between 20 and 30 W (p < 0.001). Temperatures reached 43°C in three patients applying 20 W and in eight patients applying 30 W. The shortest activation-time until threshold was 12 and 28 seconds with 30 and 20 W settings, respectively. When reaching 43°C, temperatures remained above this threshold for an additional 29 seconds on average. There was a significant correlation between IRT and renal APD. For example, when 10 W was applied in the setting of APD ≤20 mm, the recorded temperature was on average 2.3°C higher compared with APD >20 mm, with the same power settings applied, p < 0.001. Conclusion: During FURSL, IRT correlates directly with power settings and is inversely correlated with renal pelvic APD. Using a sheathless approach, power settings ≥20 W should arguably be avoided, especially in the context of a nondilated renal pelvis. ClinicalTrials: The study was registered on ClinicalTrials.gov (NCT05677425).

Current Status and Prospects of Pediatric Stone Disease: A Bibliometric and Visualization Study

Pediatric stone disease, once considered rare, has emerged as a significant research area in the past two decades due to a sharp increase in its incidence. Understanding the evolving epidemiology and treatment strategies for pediatric stone disease is crucial for enhancing child health protection. This study aims to summarize the advancements in pediatric stone disease research over the last two decades through bibliometric analysis. We conducted a comprehensive search in the Web of Science Core Collection (WoSCC) for literature on pediatric stone disease from January 1, 2000 to February 20, 2024. Econometric analyses were performed using tools such as VOSviewer, CiteSpace, and the R package "bibliometrix." Our search yielded 1,208 publications, predominantly from the United States and Turkey, showing an annual increase in publications on pediatric stone disease. Leading research institutions include Dicle University, Children's Hospital of Philadelphia, and the University of Pennsylvania, with the Journal of Pediatric Urology publishing the highest number of articles. The most prolific authors were C.P. Nelson and B. Hoppe, with Caleb P. Nelson being the most co-cited author. Research themes primarily focused on risk factors and therapeutic approaches for pediatric stone disease. Emerging research hotspots are identified by keywords such as mechanism, mini-percutaneous nephrolithotomy, recurrence, and retrograde intrarenal surgery. The study forecasts a continued upward trend in global research on pediatric stone disease, with future studies likely to delve deeper into risk factors and novel therapeutic methods.

A retrospective cohort study, analyzing trends in management of upper urinary tract stones in the adult Israeli population

OBJECTIVE

To assess trends of surgical intervention in adults with upper urinary tract stones in Israel.

METHODS

A retrospective cohort study utilizing administrative databases held at Clalit Health Services, to identify all adults (⩾18 years) who underwent their first surgical treatment for upper tract urolithiasis. Descriptive statistics were employed to summarize baseline patient demographics and surgical trends were analyzed using the Cochrane-Armitage test for trend.

RESULTS

Between 2003 and 2020, 36,624 adult patients were treated surgically for upper tract urinary stones. Mean age was 53.6 years (SD16.1). During the period investigated, the number of insured by Clalit Health Services increased by 25% and the total number of surgically treated stones increased by 98.7%. By type of procedure: Ureteroscopy (URS) increased by 351%, percutaneous nephrolithotripsy (PCNL) increased by 67%, shockwave lithotripsy (SWL) declined by 79%. The number of procedures per 100,000 population grew from to 37.5 in 2003 to 58.05 in 2022. The percentage increase in total number of surgical procedures was 103% and 90% in males and females, respectively.

CONCLUSIONS

Our findings reveal significant increases in the total number of surgically treated stones over the investigated period. Notably, this increase far outpaced the growth in the number of individuals insured by Clalit Health Services. Further research and interventions are warranted to explore the underlying factors driving these trends and to develop targeted approaches for prevention, early detection, and minimally invasive treatment of upper urinary tract stones in Israel.

A Good Craftsperson Knows Their Tools: Understanding of Laser and Ureter Mechanics in Training Urologists

Introduction: Recent decades have seen a move to minimally invasive techniques to manage urolithiasis. Trainees are expected to develop competency in common endourology procedures. Knowledge of ureter mechanics and the theory behind new technologies is important to ensure safe and efficient techniques. We aim to evaluate the exposure to endourology, self-reported competency in common techniques and knowledge of basic ureter biomechanics and technology in training urologists. Methods: An online survey was circulated to all training urologists in the Republic of Ireland. Questions focused on self-reported competency, clinical knowledge, ureter mechanical properties and laser technology. Results: Thirty responses were received with a range of 1-8 years of urology experience (mean=4 years). The respondents reported high levels of exposure to endourology with the majority reporting competency in flexible ureterorenoscopy (FURS) (n=18, 60%) and semi-rigid ureteroscopy (URS) (n=21, 70%). The respondents demonstrated good clinical knowledge but variable knowledge of laser settings, laser thermodynamics and ureter mechanics. Half of the respondents (n=15, 50%) correctly described fragmentation laser settings, with 10 trainees (n=33%) accurately identifying both factors that increase ureteral access sheath (UAS) insertion force. Most of the respondents (n=20, 67%) described the proximal ureter as the site with the greatest compliance, while the site of the greatest force during ureteroscope insertion was correctly identified by 17% (n=5). Conclusion: To our knowledge, this represents the first study evaluating urologist understanding of laser technology and the mechanical properties of the human ureter. Despite trainees reporting high levels of experience in endourology, there is a variable understanding of the principles of laser technology and ureter mechanics. Further research and education are needed with a focus on laser safety, suitable laser settings and the safe limit of insertion forces.

Device Failure and Adverse Events Related to Single-use and Reusable Flexible Ureteroscopes: Findings and New Insights From an 11-Year Analysis of the Manufacturer and User Facility Device Experience Database

OBJECTIVE

To catalog and characterize device failures and adverse events related to flexible ureteroscopes from a national database.

METHODS

Search of the Manufacturer User and Facility Device Experience database was performed for all recorded events related to flexible ureteroscopes between 2012 and 2022. The following information was collected: Problem and cause, timing, complications and injury, prolonged anesthesia, and early termination of procedure. Event severity was graded using a validated tool.

RESULTS

A total of 206 events were identified (reusable/single use ratio, 2.5:1). There were 20 different problem categories reported, which included image loss (26.7%), difficulty removing scope (13.6%), scope damage from basket (4.4%), detachment of scope tip (5.8%) and contamination (4.9%). Faulty device was the predominant cause for an event related to single-use scopes (86.4%); this was seldom the case for reusable (2%). Patient injury occurred in 21.8%, but these were all in reusable scopes. No deaths were reported, but major complications included complete avulsion of the ureter (3.4%) and fully entrapped scope necessitating open surgery (2.9%). While the safety profile for single-use scopes was superior, they were significantly more likely to result in early termination (71.1% vs 37.3%, P < .001). This was related to 76.3% of the single-use scopes experiencing sudden image loss.

CONCLUSION

Flexible ureteroscopes are fragile, and a multitude of problems can occur. Many of these can be avoided through correct surgeon technique and robust maintenance services.

Finding the optimal candidate for shock wave lithotripsy: external validation and comparison of five prediction models

We aimed to externally validate five previously published predictive models (Ng score, Triple D score, S3HoCKwave score, Kim nomogram, Niwa nomogram) for shock wave lithotripsy (SWL) single-session outcomes in patients with a solitary stone in the upper ureter. The validation cohort included patients treated with SWL from September 2011 to December 2019 at our institution. Patient-related variables were retrospectively collected from the hospital records. Stone-related data including all measurements were retrieved from computed tomography prior to SWL. We estimated discrimination using area under the curve (AUC), calibration, and clinical net benefit based on decision curve analysis (DCA). A total of 384 patients with proximal ureter stones treated with SWL were included in the analysis. Median age was 55.5 years, and 282 (73%) of the sample were men. Median stone length was 8.0 mm. All models significantly predicted the SWL outcomes after one session. S3HoCKwave score, Niwa, and Kim nomograms had the highest accuracy in predicting outcomes, with AUC 0.716, 0.714 and 0.701, respectively. These three models outperformed both the Ng (AUC: 0.670) and Triple D (AUC: 0.667) scoring systems, approaching statistical significance (P = 0.05). Of all the models, the Niwa nomogram showed the strongest calibration and highest net benefit in DCA. To conclude, the models showed small differences in predictive power. The Niwa nomogram, however, demonstrated acceptable discrimination, the most accurate calibration, and the highest net benefit whilst having relatively simple design. Therefore, it could be useful for counselling patients with a solitary stone in the upper ureter.

Personalized Prediction of Patient Radiation Exposure for Therapy of Urolithiasis: An Application and Comparison of Six Machine Learning Algorithms

The prediction of radiation exposure is an important tool for the choice of therapy modality and becomes, as a component of patient-informed consent, increasingly important for both surgeon and patient. The final goal is the implementation of a trained and tested machine learning model in a real-time computer system allowing the surgeon and patient to better assess patient's personal radiation risk. In summary, 995 patients with ureterorenoscopy over a period from May 2016 to December 2019 were included. According to the suggestions based on actual literature evidence, dose area product (DAP) was categorized into 'low doses' ≤ 2.8 Gy·cm² and 'high doses' > 2.8 Gy·cm² for ureterorenoscopy (URS). To forecast the level of radiation exposure during treatment, six different machine learning models were trained, and 10-fold crossvalidated and their model performances evaluated in training and independent test samples. The negative predictive value for low DAP during ureterorenoscopy was 94% (95% CI: 92-96%). Factors influencing the radiation exposure were: age (p = 0.0002), gender (p = 0.011), weight (p < 0.0001), stone size (p < 0.000001), surgeon experience (p = 0.039), number of stones (p = 0.0007), stone density (p = 0.023), use of flexible endoscope (p < 0.0001) and preoperative stone position (p < 0.00001). The machine learning algorithm identified a subgroup of patients of 81% of the total sample, for which highly accurate predictions (94%) were possible allowing the surgeon to assess patient's personal radiation risk. Patients without prediction (19%), the medical expert can make decisions as usual. Next step will be the implementation of the trained model in real-time computer systems for clinical decision processes in daily practice.

Ureteroscopy and Shock Wave Lithotripsy Trends from 2012 to 2019 Within the US Medicare Dataset: Sharp Growth in Ureteroscopy Utilization

Introduction and Objective: Both ureteroscopy (URS) and shock wave lithotripsy (SWL) are cornerstones in the surgical management of urolithiasis in the United States. We hypothesized that URS utilization outpaced SWL utilization in recent years and quantified the magnitude of change over time for caseloads of URS and SWL among urologists from a national Medicare database. Methods: Using the public "Medicare Physician & Other Practitioners" database (https://data.cms.gov), we determined case numbers of SWL (current procedural terminology [CPT] 50590) and URS (CPT 52356 or 52353) from 2012 to 2019. In a subanalysis, we identified "high-volume stone urologists" as those in the upper quartile of case numbers for both SWL and URS in baseline years of either 2012 or 2013 and trended their caseload from 2012 to 2019. Linear estimation models assessed annual rates of change and their statistical significance. Results: In 2012, urologists performed 41,135 SWL procedures vs 21,184 URS. URS overtook SWL in 2017 and by 2019 was the dominant modality (60,063 URS vs 43,635 SWL). Between 2012 and 2019, total URS cases annually increased by 5700 (15%/year, p < 0.001), while the number of SWL cases peaked in 2015 and has since declined on average -1.6%/year (p = 0.020). The number of urologists performing URS steadily rose from 1147 in 2012 to 2809 in 2019, reflecting an additional 246 urologists (21%/year) performing URS annually. The caseload of high-volume stone urologists showed similar trends with average URS cases increasing by 2.9/year/urologist (9.8%/year, p < 0.001) and average SWL cases declining by 0.9/year/urologist (-1.7%/year, p = 0.023). Conclusions: URS utilization has increased dramatically and outpaced SWL utilization from 2012 to 2019 within the Medicare population. URS was increasingly used by both the general urologist population and high-volume stone urologists while SWL utilization has begun to decline.

Trends and patterns of initial percutaneous nephrolithotomy and subsequent procedures among commercially-insured US adults with urinary system stone disease: a 10-year population-based study

PURPOSE

To describe trends and patterns of initial percutaneous nephrolithotomy (PCNL) and subsequent procedures from 2010 to 2019 among commercially-insured US adults with urinary system stone disease (USSD).

METHODS

Retrospective study of administrative data from the IBM® MarketScan^® Database. Eligible patients were aged 18-64 years and underwent PCNL between 1/1/2010 and 12/31/2019. Measures of interest for analysis of trends and patterns included the setting of initial PCNL (inpatient vs. outpatient), percutaneous access (1 vs. 2-step), and the incidence, time course, and type of subsequent procedures (extracorporeal shockwave lithotripsy [SWL], ureteroscopy [URS], and/or PCNL) performed up-to 3 years after initial PCNL.

RESULTS

A total of 8,348 patients met the study eligibility criteria. During the study period, there was a substantial shift in the setting of initial PCNL, from 59.9% being inpatient in 2010 to 85.3% being outpatient by 2019 (P < 0.001). The proportion of 1 vs. 2-step initial PCNL fluctuated over time, with a low of 15.1% in 2016 and a high of 22.0% in 2019 but showed no consistent yearly trend (P = 0.137). The Kaplan-Meier estimated probability of subsequent procedures following initial PCNL was 20% at 30 days, 28% at 90 days, and 50% at 3 years, with slight fluctuations by initial PCNL year. From 2010 to 2019, the proportion of subsequent procedures accounted for by URS increased substantially (from 30.8 to 51.8%), whereas SWL decreased substantially (from 39.5 to 14.7%) (P < 0.001).

CONCLUSIONS

From 2010 to 2019, PCNL procedures largely shifted to the outpatient setting. Subsequent procedures after initial PCNL were common, with most occurring within 90 days. URS has become the most commonly-used subsequent procedure type.

Paediatric kidney stone surgery: state-of-the-art review

While urolithiasis in children is rare, the global incidence is rising, and the volume of minimally invasive surgeries being performed reflects this. There have been many developments in the technology, which have supported the advancement of these interventions. However, innovation of this kind has also resulted in wide-ranging practice patterns and debate regarding how they should be best implemented. This is in addition to the extra challenges faced when treating stone disease in children where the patient population often has a higher number of comorbidities and for example, the need to avoid risk such as ionising exposure is higher. The overall result is a number of challenges and controversies surrounding many facets of paediatric stone surgery such as imaging choice, follow-up and different treatment options, for example, medical expulsive therapy, shockwave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy. This article provides an overview of the current status of paediatric stone surgery and discussion on the key topics of debate.

Renal stone density on native CT-scan as a predictor of treatment outcomes in shock wave lithotripsy

Extracorporeal shock wave lithotripsy (ESWL) is considered a standard treatment for nephrolith or kidney stones measuring less than 20 mm. Anatomical, machine-related, and stone factors play pivotal roles in treatment outcomes, the latter being the leading role. This paper examined the relationship between stone density on native CT scans and ESWL treatment to remove renal stones concerning several treatments. One hundred and twenty patients (64 males and 56 females) were enrolled and completed the study from April 2019 to September 2020. Inclusion criteria were a single renal pelvis stone of 5-20 mm to be treated for the first time in adult patients with no urinary or musculoskeletal anatomical abnormalities. We assessed patients' renal function and obtained stone characteristics using a native CT scan. Patients were then scheduled for ESWL by the same machine and operator under fluoroscopy, with two-week intervals between treatment sessions when more than one treatment session was required. Before each new session, a new KUB-US was performed to reevaluate the stone. One hundred and twenty patient records were analyzed, 64 (53.3%) males and 56 (46.7%) females, with a mean age of 38.6 years and a mean stone size of 13.15 mm. Treatment with ESWL cleared stones in 76 (63.3%) patients, while 44 (36.7%) failed the treatment. The mean stone density in patients whose stones were cleared was significantly lower (661 vs. 1001) (P<0.001). Estimating renal calculus (or kidney stone) density on a native CT scan might help prognosticate ESWL treatment outcomes regarding stone clearance rates and the number of sessions required to clear a stone.

Safety and efficacy of extracorporeal shock wave lithotripsy vs. flexible ureteroscopy in the treatment of urinary calculi: A systematic review and meta-analysis

Objective

This study aims to compare the safety and efficacy of extracorporeal shock wave lithotripsy (SWL) and flexible ureteroscopy lithotripsy (f-URS) in treating urinary tract stones.

Methods

We systematically searched PubMed, Embase, and Cochrane for literature comparing SWL with f-URS. The primary outcomes we focused on were stone-free rate (SFR) and complications; the secondary outcomes were operation time, hospital stay, retreatment rate, number of sessions, and auxiliary procedures rate. We used ReviewManager version 5.4.1 and STATA version 14.2 for meta-analysis.

Results

Seventeen studies with a total of 2,265 patients were included in the meta-analysis, including 1,038 patients in the SWL group and 1,227 patients in the f-URS group. The meta-analysis indicated that patients in the f-URS group had higher SFR than those in the SWL group [odds ratio (OR): 2.00, 95% confidence interval (CI): 1.29-3.12, p = 0.002]. In addition, we found no significant difference in complications (OR: 1.08, 95% CI: 0.85-1.37) between the two treatments. Also, we found that the retreatment rate and the auxiliary procedure rate in the f-URS group were significantly lower than those in the SWL group (OR: 0.08, 95% CI: 0.02-0.24, p < 0.00001; OR: 0.30, 95% CI: 0.11-0.83, p = 0.02). Moreover, the number of sessions in the f-URS group was significantly lower than that in the SWL group [mean difference (MD): -1.96, 95% CI: -1.55 to -0.33, p = 0.003]. However, the operation time and hospital stay in the f-URS group were significantly longer than those in the SWL group (MD: 11.24, 95% CI: 3.51-18.56, p = 0.004; MD: 1.14, 95% CI: 0.85-1.42, p < 0.00001).

Conclusion

For 1-2-cm urinary stones, f-URS can achieve a higher SFR than SWL while having a lower retreatment rate, number of sessions, and auxiliary procedure rate. For urinary stones <1 cm, there was no significant difference in SFR between SWL and f-URS groups. The SWL group has a shorter operative time and hospital stay than the f-URS group.

Temperature profiles during ureteroscopy with thulium fiber laser and holmium:YAG laser: Findings from a pre-clinical study

OBJECTIVE

The aim of this study was to investigate temperature profiles in both the renal pelvis and parenchyma during Thulium Fiber Laser (TFL) and Holmium:yttrium-aluminium-garnet (Ho:YAG) laser activation in an ex-vivo porcine model.

METHODS

Three porcine kidneys with intact renal pelvis and proximal ureters were used in the study. A temperature sensor was inserted through a nephrostomy tube into the renal pelvis and a second sensor was inserted directly into the renal parenchyma. Temperatures were recorded during continuous laser activation for 180 s, and for an additional 60 s after deactivation. TFL (150 μm and 200 μm) and Ho:YAG (270 μm) laser delivered power at settings of 2.4 W, 8 W, 20 W and 30 W.

RESULTS

Intrapelvic temperatures correlated directly to power settings. Higher power produced higher temperatures. For example, using a 150 μm fiber at 2.4 W resulted in a 2.6 °C rise from baseline (p = 0.008), whereas using the same fiber at 20 W produced a rise in temperature of 19.9 °C (p = 0.02). Larger laser fibers caused significantly higher temperatures compared to smaller fibers using equivalent power settings, e.g. mean temperature at 20 W using 150 μm was 39.6 °C compared to 44.9 °C using 200 μm, p < 0.001. There was a significant increase in parenchymal temperatures when applying 20 W and 30 W of laser power with the two larger fibers.

CONCLUSION

In this ex-vivo study, renal temperatures correlated directly to power settings. Higher power produced higher temperatures. Furthermore, larger laser fibers caused higher temperatures. These findings could help guide selection of safe power settings for ureteroscopic lithotripsy, but future clinical studies are needed for confirmation.

Efficacy of Flexible Ureteroscopic Lithotripsy and Percutaneous Nephrolithotomy in the Treatment of Complex Upper Urinary Tract Nephrolithiasis

Objective

A case-control study was conducted to compare the efficacy and prognostic factors of flexible ureteroscopic lithotripsy (FURL) and percutaneous nephrolithotomy (PCNL) when treating complex upper urinary tract renal calculi based on a retrospective cohort study.

Methods

The study period was from October 2019 to December 2021. A retrospective study was carried out on 100 patients with complicated upper urinary tract nephrolithiasis who underwent surgery in the Urology Department of our hospital. They were assigned into two groups: FURL and PCNL groups. The intraoperative blood loss, operation time, hematuria duration, hospital stay, primary stone removal rate, incidence of intraoperative and postoperative complications, VAS score, level of inflammatory factors, and micturition function were compared. According to the postoperative prognosis, the patients were reassigned into two groups: good prognosis group (n = 38) and poor prognosis group (n = 106). The factors related to poor prognosis after FURL and PCNL were screened, and multivariate loglistic regression analysis was adopted to determine the risk factors.

Results

The primary stone clearance rate in the PCNL group was significantly higher than that in the FURL group, and there was no significant difference in the incidence of intraoperative and postoperative complications between the two groups (P > 0.05). The intraoperative blood loss and the duration of hematuria in the PCNL group were significantly shorter than those in the FURL group, and the operation time and postoperative hospital stay in the FURL group were longer than those in the FURL group. The postoperative VAS score in the study group was significantly lower than that in the control group (P < 0.05). The levels of CRP, IL-1, TNF-α, and NF-κB in both groups decreased after operation, and the level of inflammatory factors in the PCNL group was significantly lower than that in the FURL group (P < 0.05). The indexes of IPSS and Q max in the PCNL group were significantly lower than those in the control group 3 months after operation. The index of micturition function in the PCNL group was significantly lower than that in the FURL group. Preoperative use of immunosuppressant, preoperative stone fever, positive preoperative urine culture, preoperative urinary leukocyte count ≥ 544 × L, intraoperative urinary opacity, and pus fur were significantly correlated with poor prognosis of ureteral patients (P < 0.05). Preoperative stone fever, high preoperative urinary leukocyte count, intraoperative urinary turbidity, and suppurative fur were independent risk factors for postoperative SIRS in patients with ureteral calculi.

Conclusion

PCNL is effective when treating complex upper urinary tract renal calculi. Compared with FURL, PCNL can remarkably reduce intraoperative blood loss and hematuria duration, can enhance micturition function, and will not remarkably increase the incidence of intraoperative and postoperative complications, high safety. High white blood cell count in urine before operation, fever due to stone before operation, turbid urine, and purulent fur during operation are independent risk factors for postoperative adverse outcome in patients with complex upper urinary tract renal calculi. Patients should be fully treated before surgery.

[Impact of the COVID-19 pandemic on urology residency training programs in Germany]

BACKGROUND

Several international medical societies reported a negative impact on urology residency training programs due to the COVID-19 pandemic.

OBJECTIVES

The aim of this study was to investigate the impact of the pandemic on urological residency in Germany.

MATERIALS AND METHODS

From the 20^th of May 2020 until the 20^th of June 2020, a Germany-wide online survey on the continuing residency training was distributed via the members of the working group, social media (Facebook, Twitter, Instagram) and the German Society of Residents in Urology (GeSRU e.V.) newsletter. The survey covered 3 topics: 1) basic characteristics of the participants, 2) general and 3) subjective influence of the COVID-19 pandemic on clinics and further residency training.

RESULTS

A total of 50 residents took part in the survey; 54% were women. The median age was 31 years. Most of the participants were in their 2nd (22%) and 5th (26%) year of training and worked in a university hospital (44%) or in a clinic of maximum care (30%). 38% of the respondents stated that they only served urological emergencies during the COVID-19 pandemic. For 28% this meant a very large delay (80-100%) in the specialisation, while 28% stated only a minor impact. 66% documented training impairments caused by fewer operations, low patient numbers in the outpatient department (50%), congress (50%) and workshop (44%) cancellations. 46% of residents reported direct contact with COVID-19 patients while 10% were deployed on interdisciplinary IMC units. Numerous physical distancing and hygiene measures have been implemented by the clinics.

CONCLUSION

On average, around 50% of the urology residents indicated significant restrictions in training due to the COVID-19 pandemic in Germany. The delay in training cannot currently be measured in units of time, but it can be assumed that training for residents during the pandemic is likely to be of a lower quality compared to previous generations.

Neural Networks Modeling for Prediction of Required Resources for Personalized Endourologic Treatment of Urolithiasis

When scheduling surgeries for urolithiasis, the lack of information about the complexity of procedures and required instruments can lead to mismanagement, cancellations of elective surgeries and financial risk for the hospital. The aim of this study was to develop, train, and test prediction models for ureterorenoscopy. Routinely acquired Computer Tomography (CT) imaging data and patient data were used as data sources. Machine learning models were trained and tested to predict the need for laser lithotripsy and to forecast the expected duration of ureterorenoscopy on the bases of 474 patients over a period from May 2016 to December 2019. Negative predictive value for use of laser lithotripsy was 92%, and positive predictive value 91% before application of the reject option, increasing to 97% and 94% after application of the reject option. Similar results were found for duration of surgery at ≤30 min. This combined prediction is possible for 54% of patients. Factors influencing prediction of laser application and duration ≤30 min are age, sex, height, weight, Body Mass Index (BMI), stone size, stone volume, stone density, and presence of a ureteral stent. Neuronal networks for prediction help to identify patients with an operative time ≤30 min who did not require laser lithotripsy. Thus, surgical planning and resource allocation can be optimised to increase efficiency in the Operating Room (OR).